Electrosurgical probe and kit and method of using

ABSTRACT

Electrosurgical probes for treating tissue, and surgical procedures that make use of such probes. Such a probe includes a working element having a core member, a sheath secured to the working element, and a conductor disposed in a first internal longitudinal channel of the core member and having an active electrode coupled thereto. The sheath has a passage in which the core member is disposed, and the passage has an opening at a distal end of the sheath. The conductor is reciprocable within the sheath and adapted to carry a radio frequency current to and from the active electrode, which extends from the opening at the distal end of the sheath. An irrigation channel is defined by a second internal longitudinal channel of the core member. The electrosurgical probe is marked as disposable and not for reuse in a medical procedure performed on more than one patient.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a division patent application of U.S. patent application Ser.No. 14/716,150, filed May 19, 2015, now U.S. Pat. No. 10,070,917, whichclaims the benefit of U.S. Provisional Application No. 62/000,262, filedMay 19, 2014. The contents of these prior applications are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to electrosurgical probes for treatingdamaged, diseased or enlarged tissue, and to surgical procedures thatmake use of such probes.

Electrosurgical effects can be accomplished by applying a highly dampedradio frequency (RF) current to tissue through an electrode in the formof an active (+) electrode (tip) of an electrosurgical (electrocautery)probe, from which the RF current flows to a ground (−) electrode. RFelectrosurgical probes (RF probes), such as those commonly used inurological and hysteroscopic procedures, are said to be monopolar orbipolar or said to have a monopolar or bipolar operating mode, dependingon their electrode configuration. RF probes operating in a monopolarmode utilize a single (active) electrode (tip) and rely on externalgrounding of a patient (e.g., a ground electrode in the form of apatient plate) to cause current flow from the active electrode to tissueof the patient. RF probes operating in a bipolar mode have twoelectrodes, typically designated as active and return electrodes, andcurrent flow is localized between these electrodes. As it passes throughtissue from the active electrode to the ground or return electrode, theRF current resects (cuts), coagulates and/or ablates (desiccates) thetissue, depending on the type of probe and the RF power and wave lengthcombinations used. RF electrosurgical probes are typically placedthrough a resectoscope (used in urological procedures), hysteroscope(used in gynecological procedures) or other device, which is oftenequipped with a telescope so that the active electrode of the probe isin direct view of the surgeon at all times. Irrigating solutions arecommonly used as a distention medium and a coolant for the activeelectrodes of RF probes during electrosurgical procedures.

Resectoscopes and hysteroscopes (hereinafter referred to aselectrosurgical probes) have been used for decades to diagnose and treatmedical conditions in the human bladder and the uterus, respectively.Electrosurgical resection refers to procedures by which damaged,diseased or enlarged tissue is removed with an electrosurgical probe. Anonlimiting example is transurethral resection of the prostate (TURP),in which prostate tissue is removed by means of an active electrode (forexample, a cutting loop) passed through the urethra by means of aresectoscope. This procedure has served as the historical treatment ofbenign prostate hypertrophy (BPH)), commonly known as “enlargedprostate,” and prostatitus. Bladder tumors and cysts in men and womenare also treated by electrosurgical resection. Electrosurgical ablationrefers to procedures by which an electrosurgical probe is used to ablate(dessicate) tissue, which eventually sloughs off instead of beingimmediately removed on contact with the electrode. A nonlimiting exampleof an electrosurgical ablation procedure is endometrial ablation totreat endometriosis in women, in which tissue is removed by means ofroller that serves as the active electrode. Another example istransurethral ablation of the prostate (TUAP), in which prostate tissueis ablated by means of an electrocautery probe passed over astylet/obturator or guide wire, through the prostatic urethra.

In addition to its electrode, an electrosurgical probe typicallyincludes a working element equipped with a power cord for connection toan RF electrosurgical current generator, and a sheath that extends fromthe working element and through which one or more conductors are routedto deliver RF current to the electrode protruding from a distal end ofthe sheath. The probe is also typically equipped with a telescope and/orlight source disposed in one or more internal channels within the sheathto allow direct vision during placement and use of the probe. Theelectrode and its conductor(s) may be capable of reciprocal movementwithin the sheath through the operation of an actuation lever of theworking element. The sheath may also define an internal flow channel toenable an irrigation fluid to be delivered for immersion cooling of theelectrode. The RF generator, light source, and telescope are capitalequipment and available in a typical surgical suite. Whileelectrosurgical probe electrodes are disposable and therefore do notrequire sterilization after use, the remaining components of aelectrosurgical probe, including the working element, sheath andtelescope, are typically formed of stainless steels or another durablemetallic material and durable heat-resistant plastics that enable thesecomponents to be reused following re-sterilization, for example, usingan autoclave and/or ethylene oxide gas. As such, electrosurgical probestypically have high initial purchase costs. The distal end of the sheathis often equipped with a plastic tip that becomes damaged over time, insome cases after a single use, as a result of the high RF currentlevels, necessitating that the sheath undergo an expensive andtime-consuming repair. Also due to the RF currents, metal components ofan electrosurgical probe require electrical insulation to protect thesurgeon from receiving shocks and burns during use of the probe. Evenso, surgeons are commonly required to wear two pairs of latex gloves asa safety precaution.

Sterilization can be a complicated process, particularly in view of theinternal channels within the sheath that accommodate a light source,telescope, and/or cooling flow stopcocks and channels. Furthermore,components of reusable electrosurgical probes are conventionallyindividually reprocessed, sterilized, and packaged, and then kept indrawers, cabinets, and carts accessible to the surgical team. If any ofthe components are unavailable or the wrong size, the procedure cannotgo forward. Generally, hospitals have additional electrosurgical probeson hand in case one fails during surgery. However, at times when caseloads are high, a physician may be forced to either wait for anotherunit to be sterilized or cancel the surgery.

ISO regulations require disposable (i.e., single-use) medical devices tobe marked with the

symbol to indicate that the devices are disposable and not for reuse ina medical procedure performed on more than one patient. Since the late1980's, the use of disposable (sterile, one-time use) surgicalinstruments and devices has dramatically increased in the United States.This trend of cycling from reusable to disposable surgical instrumentsand devices is taking place now in countries around the world as theireconomies grow, as is the awareness of the risks and costs associatedwith hospital-acquired infections, especially those in the operatingroom. This trend is driven by numerous factors, such as sterilityassurance, quality/performance, reducing cross contamination, and costfactors (cost control, convenience, and patient charges).

BRIEF DESCRIPTION OF THE INVENTION

The present invention provides electrosurgical probes for treatingdamaged, diseased or enlarged tissue, and to surgical procedures thatmake use of such probes.

According to one aspect of the invention, an electrosurgical probe isprovided that includes a disposable working element comprising a coremember having a plurality of internal longitudinal channels, adisposable elongate sheath secured to the working element, and aconductor disposed in a first of the internal longitudinal channels ofthe core member and having an active electrode coupled thereto. Thesheath has a sheath passage in which the core member is disposed suchthat the sheath surrounds the core member, and the sheath passage has anopening at a distal end of the sheath. The conductor is reciprocablewithin the sheath and adapted to carry a radio frequency current to andfrom the active electrode. The active electrode extends from the openingat the distal end of the sheath and is configured to perform cutting,coagulation, or ablation of tissue when the radio frequency currentflows to the active electrode. An irrigation channel is defined by asecond of the internal longitudinal channels of the core member andconfigured to couple with an irrigation fluid source and provides anirrigation fluid to the active electrode from the irrigation fluidsource. The working element further has means for reciprocating theactive electrode relative to the sheath, and the sheath and the workingelement, including the core member and the reciprocating means thereof,are each single-use components formed of disposable materials and theelectrosurgical probe is marked as disposable and not for reuse in amedical procedure performed on more than one patient.

According to another aspect of the invention, a method of using anelectrosurgical probe to perform a medical procedure includes placingwithin a patient an active electrode of a electrosurgical probe thatcomprises a working element and an elongate sheath from which the activeelectrode protrudes, wherein the sheath and the working element are eachsingle-use components formed of disposable materials and theelectrosurgical probe is marked as disposable and not for reuse in amedical procedure performed on more than one patient. A singleelectrosurgical procedure is then performed on the patient using theactive electrode of the electrosurgical probe, after which the workingelement, the sheath, and the active electrode are discarded, such thatthe placing and performing steps are the first and only medicalprocedure in which the working element, the sheath, and the activeelectrode are used.

A technical effect of the invention is that the disposableelectrosurgical probe can be offered as a kit, in which the workingelement, sheath, core member, and one or more electrodes are alldisposable components of the kit.

Other aspects and advantages of this invention will be betterappreciated from the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view representing an electrosurgical probe inaccordance with a nonlimiting embodiment of this invention.

FIG. 2 represents an electrode protruding from a distal end of a sheathof the electrosurgical probe of FIG. 1 as a result of operating a handleof the working element.

FIG. 3 represents a partial cutaway view of the distal end of the sheathof FIG. 2, showing the electrode protruding therefrom and revealing anelectrode connection and irrigation tube within the sheath.

FIG. 4 is a perspective view of the probe of FIG. 1, showing a partialcutaway of the distal end of the sheath to reveal a core member of theprobe and components disposed therein.

FIG. 5 represents a detailed perspective view of the partial cutawayview of FIG. 4.

FIG. 6 represents an end view of the sheath and core member of the probeof FIGS. 1 through 5.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 through 6 depict an electrosurgical probe 10 in accordance witha nonlimiting embodiment of the present invention. The drawings depictthe probe 10 as a resectoscope, though other electrosurgical probescapable of use in a wide variety of procedures are also within the scopeof the invention. The probe 10 is represented as including a sheath 12through which conductors can be routed to one or more electrodesdisposed at a distal end 14 of the sheath 12. The conductors carry acurrent, preferably an RF current, generated by an electrosurgicalgenerator (not shown) that is connected to the probe 10 via a power cord16 extending from a working element 18 of the probe 10. The probe 10 canbe a monopolar or bipolar RF electrosurgical probe. FIGS. 1 through 5depict a single electrode 20 configured as a cutting loop (wire), thoughother electrode configurations are possible and within the scope of thisinvention, for example, such well-known types as ball tip, disk, rollertip, barrel, cone, point, knife, flat band, coagulating, and punctateelectrodes. As a cutting loop, the electrode 20 is represented aselectrically connected to one or more insulated conductors 21 to definean active (+) pole of the RF circuit.

The electrode 20 and its conductors 21 are preferably capable ofreciprocal movement within the sheath 12, as evidenced by the retractedand extended positions of the electrode 20 depicted in FIGS. 1 and 2,respectively. Movement of the electrode 20 and conductors 21 relative tothe sheath 12 can be effected through the operation of an actuationlever 22 of the working element 18. The electrode 20 and its conductors21 are disposed in an internal longitudinal channel 26 defined within acore member 24 that is coaxially disposed within an internal passage 25defined by the sheath 12, such that the core member 24 is completelysurrounded by the sheath 12. The electrode 20 and its conductors 21 maybe reciprocably disposed in the internal channel 26, or the core member24 may be reciprocably disposed within the passage 25 of the sheath 12.As evident from FIGS. 4 through 6, the core member 24 has acircular-shaped outer circumference defined by a tubular outer wall 28of the member 24, and an internal web 30 that defines the internalchannel 26 as well as a second internal longitudinal channel 32 in whicha telescope 34 is represented as being received to allow direct visionduring placement and use of the probe 10. The internal channels 26 and32 preferably have circular cross-sections and the core member 24 isrepresented as having a plane of symmetry through the channels 26 and32, with the result that the channels 26 and 32 are between two internallongitudinal channels 36 that are defined by the remainder of thecircular interior cross-section of the core member 24 surrounded by theouter wall 28, as seen in FIG. 6. As a result of the circularcross-sectional shapes of the outer wall 28 and channels 26 and 32 andthe symmetrical shape of the core member 24, the channels 36 aresubstantially identical mirror-images of each other and have fan-shapedcross-sections. Either or both of the channels 36 can serve as anirrigation tube that enables an irrigation fluid to be delivered to theelectrode 20, for example, to perform immersion cooling of the electrode20. Alternatively, a separate tube could be located within either orboth channels 36 through which an irrigation fluid could flow throughthe sheath 12. In either case, at least one of the channels 36 isadapted to be fluidically coupled to a fluid source, for example, viaone or more irrigation ports 38 located on the working element 18. As aresult of the channels 36 being disposed on opposite sides of thechannel 26 containing the electrode 20, the channels 36 are able todirect irrigation fluid to opposite sides of the electrode 20, therebyenveloping the electrode 20 and promoting the desired effect of theirrigation fluid in close proximity to the electrode 20.

Whereas the telescope 34, RF generator, and other such componentsincluding light sources are capital equipment of the probe 10, apreferred aspect of the invention is that the sheath 12, working element18, electrode 20, and core member 24 are disposable and intended to bediscarded after a single use, and therefore do not require sterilizationafter use and are not required to be formed of a stainless steel orother durable metallic material that would enable these components to besterilized and reused. For example, the sheath 12, working element 18,and core member 24 can be formed of polymeric materials, including butnot limited to plastics of the types commonly used for disposablesurgical components, for example, plastics manufactured in an FDA/ISOCertified Facility with FDA marketing clearance. As such, the term“disposable” is used and defined herein to mean an article that is notadapted to be cleaned, sterilized, and reused for a medical procedureperformed on a patient, and therefore is required to be marked with the

ISO symbol as a disposable (i.e., single-use) device. If the sheath 12,working element 18, and core member 24 are formed of electricallydielectric polymeric materials, the conductors 21 of the electrode 20may be routed through the sheath 12 without requiring electricalinsulation. Optionally, the distal end 14 of the sheath 12, includingthat portion of the sheath 12 that protrudes over the opening of thesheath passage 25, may be formed of or coated with a material thatoffers a greater degree of erosion and heat resistance to the high RFcurrent levels, a notable but nonlimiting example of which is aphenol-formaldehyde resin such as Bakelite. Though also intended to bedisposable, preferred materials for the electrode 20 include tungstenand stainless steels, though other materials could be used.

To facilitate use of the probe 10, the sheath 12, working element 18,electrode 20, core member 24, and telescope 34 of the probe 10 arepreferably separable, allowing the electrode 20 to be removed from thecore member 24, allowing the core member 24 to be removed from thesheath 12, and allowing the sheath 12, core member 24 and telescope 34to be separated from the working element 18. The conductors 21 for theelectrode 20 can be permanently fixed within the core member 24 orwithin the working element 18, in which case the electrode 20 canpreferably be electrically coupled and decoupled from the conductors 21and/or the conductors 21 can preferably be electrically coupled anddecoupled from the working element 18 with suitable quick-connectfeatures.

In view of the above, with the possible exception of the telescope 34,all of the components of the probe 10 depicted in FIGS. 1 through 6 areintended to be disposable. Due to being disposable, the electrosurgicalprobe 10 can reduce if not eliminate the handling, sterilization,packaging, and testing of and risk of damage to individual reusablecomponents of probes that are currently used in electrosurgicalprocedures at surgery centers and hospitals. The risk of injury and/orcontamination to the personnel involved with this process can bevirtually eliminated with the disposable electrosurgical probe 10. Theelectrosurgical probe 10 is not required to be re-sterilized after use,as is conventional with reusable electrosurgical probes, though itshould be understood that each individual disposable electrosurgicalprobe 10 would be pre-sterilized prior to use to ensure safety.Maintenance, wear due to use, and cross-contamination are also avoidedwith the disposable electrosurgical probe 10. Furthermore, it isforeseeable that the disposable electrosurgical probe 10 may be readilyadapted or adaptable to particular brands of generators and telescopes.

The electrosurgical probe 10 and its components shown in FIGS. 1 through6, as well as other optional components and materials, can be packagedtogether to form what will be referred to as a “disposableelectrosurgical kit” or simply a “kit.” The convenience and ability toaccess one kit with all the necessary components in a ready-to-usesterile package reduce the time and frustration that can be encounteredwhen attempting to ensure that an electrosurgical probe and itscomponents are available and ready to perform an electrosurgicalprocedure. Other major advantages include the ability to customize anindividual kit, for example, to provide electrodes of variousconfigurations within a single kit. In addition, the kit can offerdifferent types of tubing connections to provide secure attachment to ascope, including but not limited to a stopcock, tubing with stopcock,and/or a luer connector.

The disposable electrosurgical kit has the ability to save money, reduceprocedure time, reduce the risk of hospital-acquired infections bypatients, and reduce the risk of injury or infections to hospitalpersonnel and physicians. The functionality of the disposableelectrosurgical probe 10 and kit relative to conventional reusableelectrosurgical probes is not affected by its disposable nature, as RFgenerators, light sources, and telescopes usable with the probe 10 canbe the same as those commercially available and commonly used at surgerycenters and hospitals. As such, physicians may maintain the power andoptical equipment they are familiar with.

While the invention has been described in terms of specific embodiments,it is apparent that other forms could be adopted by one skilled in theart. For example, the physical configuration of the disposableelectrosurgical probe 10 could differ from that shown, a disposabletelescope could be used, and materials and processes other than thosenoted could be used. Therefore, the scope of the invention is to belimited only by the following claims.

The invention claimed is:
 1. An electrosurgical probe comprising: adisposable working element comprising a core member having a pluralityof internal longitudinal channels; a disposable elongate sheath securedto the working element, the sheath having a sheath passage in which thecore member is disposed such that the sheath surrounds the core member,the sheath passage having an opening at a distal end of the sheath; aconductor disposed in a first of the internal longitudinal channels ofthe core member, the conductor being reciprocable within the sheath andpermanently fixed within the core member; an active electrodeelectrically coupled to the conductor and configured to be electricallydecoupled from the conductor, the active electrode being adapted toreceive a radio frequency current from and return the radio frequency tothe conductor when electrically coupled to the conductor, the activeelectrode extending from the opening at the distal end of the sheath andbeing configured to perform cutting, coagulation, or ablation of tissuewhen the radio frequency current flows to the active electrode; and anirrigation tube defined by a second of the internal longitudinalchannels of the core member and configured to couple with an irrigationfluid source and provide an irrigation fluid to the active electrodefrom the irrigation fluid source; wherein the working element comprisesmeans for reciprocating the active electrode relative to the sheath; andwherein the sheath and the working element, including the core memberand the reciprocating means of the working element, are each single-usecomponents formed of disposable materials and the electrosurgical probeis marked as disposable and not for reuse in a medical procedureperformed on more than one patient.
 2. The electrosurgical probe ofclaim 1, further comprising a telescope disposed in a third of theinternal longitudinal channels of the core member and separable from thesheath, the working element, and the core member.
 3. The electrosurgicalprobe of claim 2, wherein the telescope is adapted to be separated fromthe sheath, the working element, and the core member and then cleaned,sterilized, and reused for a medical procedure performed on more thanone patient.
 4. The electrosurgical probe of claim 1, wherein the coremember comprises a tubular outer wall and an internal web within andintegral with the tubular outer wall that divides a cavity within thetubular outer wall into the plurality of internal longitudinal channels.5. The electrosurgical probe of claim 4, wherein the irrigation tubedefined by the second internal longitudinal channel of the core memberis a first irrigation tube, the core member comprises a third of theinternal longitudinal channels that defines a second irrigation tube,and the first irrigation tube is a mirror-image of the second irrigationtube relative to a plane of symmetry through the first internallongitudinal channel.
 6. The electrosurgical probe of claim 5, whereinthe first irrigation tube defined by the second internal longitudinalchannel and the second irrigation tube defined by the third internallongitudinal channel each have an arcuate convex outer wall defined bythe tubular outer wall of the core member and two concave internal wallsdefined by the internal web of the core member.
 7. The electrosurgicalprobe of claim 1, wherein the sheath, the working element, and theactive electrode are configured to be separable and removable from eachother.
 8. The electrosurgical probe of claim 1, wherein the core memberis configured to be removable from the sheath.
 9. The electrosurgicalprobe of claim 1, wherein the sheath is configured to be separable fromthe working element.
 10. The electrosurgical probe of claim 1, whereinthe sheath and the working element, including the core member and thereciprocating means of the working element, are each formed of anelectrically dielectric polymeric material.
 11. The electrosurgicalprobe of claim 1, wherein the conductor is disposed within the firstinternal longitudinal channel of the core member without electricalinsulation therebetween.
 12. The electrosurgical probe of claim 1,wherein a portion of the sheath protrudes over the opening of the sheathpassage, the portion of the sheath being formed of or coated with amaterial having a greater degree of erosion and heat resistance to theradio frequency current than the disposable material that forms aremainder of the sheath.
 13. The electrosurgical probe of claim 12,wherein the material of the portion of the sheath is aphenol-formaldehyde resin.
 14. The electrosurgical probe of claim 1,further comprising at least a second active electrode configured to beelectrically coupled and decoupled from the conductor.
 15. Theelectrosurgical probe of claim 1, wherein the electrosurgical probe is aurological or hysteroscopic electrosurgical probe.
 16. A method of usingthe electrosurgical probe of claim 1 as a single-use device to perform amedical procedure, the method comprising: placing the active electrodeof the electrosurgical probe within a patient; performing anelectrosurgical procedure on the patient using the electrosurgicalprobe; and then discarding the working element, the core member thereof,the sheath, and the active electrode after performing theelectrosurgical procedure, wherein the placing and performing steps arethe first and only medical procedure in which the working element, thesheath, and the active electrode are used.
 17. A medical procedurecomprising: placing within a patient an active electrode of anelectrosurgical probe, the electrosurgical probe comprising a workingelement comprising a core member, an elongate sheath that is secured tothe working element, surrounds the core member, and has an opening fromwhich the active electrode protrudes, and a conductor within the sheathand permanently fixed within the core member, wherein the activeelectrode is electrically coupled to the conductor and wherein thesheath and the working element are each single-use components formed ofdisposable materials and the electrosurgical probe is marked asdisposable and not for reuse in a medical procedure performed on morethan one patient; performing a single electrosurgical procedure on thepatient using the active electrode of the electrosurgical probe;electrically decoupling the active electrode from the conductor; andthen discarding the working element, the sheath, and the activeelectrode after performing the electrosurgical procedure, wherein theplacing and performing steps are the first and only medical procedure inwhich the working element, the sheath, and the active electrode areused.
 18. The medical procedure of claim 17, wherein the electrosurgicalprocedure is a urological or hysteroscopic procedure.